A Class-C amplifier linearized by a constant conduction angle biasing circuit

This work presents a dynamic biasing topology capable of linearizing a Class-C power amplifier (PA). The topology utilizes a control loop that senses the operating conditions of the power device by means of a scaled replica. The loop operates on the principle of keeping the conduction angle constant and thereby ensuring linearity. The work details some of the design considerations that should prove useful to a designer wanting to implement the topology in an RF integrated circuit. Measurement results from a fully-functional low-frequency prototype bring merit to the topology.